Rate-Accelerating Effect by the Neighboring-Group Participation of Protecting Groups in the Dehydrative Cyclization of 1,3,5-Triketones
作者:Akira Sakakura、Hitoshi Watanabe、Kazuaki Ishihara
DOI:10.1021/ol800860p
日期:2008.6.1
Neighboring-group participation of an acyl protecting group efficiently promotes the Bronsted acid-catalyzed dehydrative cyclization of 1,3,5-triketones to gamma-pyrones, whereas a bulky silyloxy group in the beta-position retards the cyclization. This reaction provides an efficient synthetic route for a common intermediate for the synthesis of gamma-pyrone-containing bioactive natural products.
酰基保护基团的相邻基团参与有效地促进了1,3,5-三酮的布朗斯台德酸催化的脱水环化为γ-吡喃酮,而β位置上的庞大甲硅烷基氧基则阻碍了环化反应。该反应为合成含γ-吡喃酮的生物活性天然产物的普通中间体提供了有效的合成途径。